Anti-platelet therapy in ST-elevation myocardial infarction patients: balancing ischaemic and bleeding risk

Dual anti-platelet therapy (DAPT) is fundamental for maintenance medication and required for a defined period of time following stent implantation by percutaneous coronary intervention (PCI) to prevent stent thrombosis and subsequent myocardial infarction. 1 The European Society of Cardiology (ESC) published a dedicated 'Focused Update DAPT 2017', which summarizes the current standard in individualized anti-platelet therapy 2 along with the respective guidelines for patients with ST-elevation myocardial infarction (STEMI) 3 and non-STEMI 4 and for myocardial revascularization. 5The guidelines recommend a standard 12-month duration of DAPT using a potent P2Y12 inhibitor in addition to acetyl-salicylic acid (ASA).Several trials investigated intensified and/or prolonged anti-thrombotic treatment in patients with recent myocardial infarction (summarized in Table 1): overall, these trials exposed patients to an intensified or prolonged anti-thrombotic regimen.More intense anti-thrombotic treatment translated into more major bleedings.While selecting patients with increased ischaemic risk, a relevant proportion of patients suffered bleedings or was at least at an increased bleeding risk.Several scores were developed to identify higher risk for bleeding, such as the PRECISE-DAPT score, 6 or ischaemia, such as the ESC risk stratification in chronic coronary syndromes (CCS) 7 or the CHADS-P 2 A 2 RC score. 8reating patients with DAPT in general is a dynamic process 9 as changes in ischaemic or bleeding risk might require re-evaluation of indication and duration of DAPT.The essential principle is weighing risk and benefit of DAPT.Therefore, guidelines recommend to re-evaluate composition, dose, and duration, as soon as a relevant change in risk occurs during DAPT. 2 It is recommended to assess the presumed bleeding risk by PRECISE-DAPT score and to use a score value of ≥25 points to shorten DAPT duration. 6n order to evaluate patients for increased ischaemic risk, the ESC risk stratification model 7 and, more recently, the CHADS-P 2 A 2 RC score 8 are the most recommended ones.Both were used in a large Danish cohort of stable patients undergoing and the CHADS-P 2 A 2 RC score was the superior strategy in CCS. 10 Nevertheless, ESC guidelines suggest optional continuation of DAPT > 12-30 months in patients following an acute coronary syndrome (ACS) based on an individual risk assessment, if DAPT has been well tolerated without bleeding complications and if patients are judged to have a low bleeding risk but a high thrombotic